Diffusion

cryptography

Definition

Diffusion

Diffusion is the property of a cipher that spreads the influence of every bit of the plaintext and key over as many bits of the ciphertext as possible. Changing one bit in the plaintext or key should trigger a change in approximately half of the ciphertext bits.

Avalanche Effect

Definition

Avalanche Effect

The avalanche effect is the property of a cipher that a small change in the input (one bit of plaintext or key) causes a significant change in the output. In a well-designed cipher, flipping one input bit should change approximately half of the output bits.

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